Lines like "Another winner!" and "This year's hottest new star!" were used on posters for films The Animal and A Knight's Tale, both of which have been recently released in the United States.
But the critic who supposedly wrote them - David Manning of the Ridgefield Press - has been revealed as a figment of a Sony marketing executive's imagination.
Manning's quotes were also used to sell Vertical Limit, starring Chris O'Donnell, and Kevin Bacon's Hollow Man.
But despite an atmosphere of hype and stunts, this "certainly does cross the line" of acceptability, Dick Cook, chairman of the Walt Disney Motion Pictures Group, said.
"We would never, never, never, ever do that," he told the magazine.
The Ridgefield Press is a real weekly newspaper covering a small town in Connecticut.
But it does not have a reviewer called David Manning, and it was not aware that its name was being used on film adverts.
An unidentified Sony employee apparently concocted the Manning persona last July, using the name of a friend.
Ms Tick said Sony was looking into it and would "take appropriate action".
"If he doesn't exist, he should at least have given us a better quote," Joe Roth, whose Revolution Studios produced The Animal, said.
'Disappointing'
Sony also broke convention by paying cinemas to show trailers of The Animal.
"They should be paying audiences to sit through this disappointing, half-baked comedy," said one real reviewer on E! Online.
A Knight's Tale needed a little less help, but was still described as "a forgettable, somewhat corny romantic adventure" by the Hollywood Reporter's Kirk Honeycutt.
It has taken almost $50m (£35m) at America's box offices, while The Animal took $20m (£14m) in its first weekend.